The general objective of this study is to analyse the functional status of tumor-associated macrophages in human ovarian tumors. Macrophages are isolated from ascitic and solid ovarian tumors. Their cytotoxicity is measured in vitro against a tumor cell line. Moreover, the susceptibility of primary ovarian carcinoma cultures to macrophage cytotoxicity is being studied. Agents such as Interferons, lymphokines and endotoxin enhance the cytotoxicity of human monocytes and macrophages and we are investigating the responsiveness to these stimuli of macrophages from human ovarian tumors.